Randy Couture first revealed the signing Monday to ESPN's MMA Live and Strikeforce has since confirmed the bout details.
Ryan's opponent on Aug. 13 will be another fighter making his pro debut, Lucas Stark. Stark comes from a wrestling background and has competed numerous times locally for the Rage in the Cage promotion.
The 27-year-old Ryan trains out of his dad's Xtreme Couture in Las Vegas, where he also works as a gym manager.
Ryan fought to a controversial draw against 10th Planet jiu-jitsu black belt Sean Bollinger this past March, closing out his own amateur MMA career with a record of 5-1-1.